03 Wednesday Jun 2026
Posted in insects
They emerged a few days later than last year but, as the temperatures rose – if you haven’t caught up with the news, the UK has just experienced a heat wave, with the hottest May temperatures ever recorded, the Marsh fritillaries began to fly at the local nature reserve where a colony was illegally established three years ago.
These butterflies shouldn’t exist where they do but they certainly are a stunning sight to behold.
23 Saturday May 2026
Posted in insects
Tags
Adonis blue, blue butterflies, British butterflies, butterflies in Tout Quarry, butterflies on the Isle of Portland, butterfly, Dorset butterflies, Isle of Portland butterflies, Polyommatus bellargus
As the Adonis blue (Polyommatus bellargus) uses Horseshoe vetch (Hippocrepis comosa) as its larval food plant, it can only be found where that species of vetch grows, which in turn means the majority of this butterfly’s colonies are restricted to certain locations in southern England, specifically ‘in the core areas of chalk downland in Dorset, Wiltshire, Sussex and the Isle of Wight’, according to Life Cycles of British & Irish Butterflies. (Horseshoe vetch will feature in tomorrow’s blog post.)
The restriction imposed by its larval plant means I never see this butterfly in Wales, and so, last week, on the Isle of Portland, was only the fourth time I’d seen the stunning cobalt blue upper wings of the male Adonis blue.
And, as this was the very start of their 2026 season – there are two generations of adults each year, the first fly in May-June, the second in August-September – I only saw three individuals, all males. The females emerge a little later than the males, so, due to poor timing on my part, I’ve only once seen a female Adonis blue, back in August 2019, during a visit to the Malling Down Reserve in East Sussex. Though I already have another trip to Weymouth and Portland booked, that will be in July, so I will once again miss seeing any females. I intend trying to remedy that omission next year, as I would very much like to be present when more of these little stunners are in flight, both male and female.
20 Wednesday May 2026
Posted in nature
Tags
British butterflies, butterfly, Cupido minimus, Dorset butterflies, Isle of Portland butterflies, Small blue, Small blue butterfly, Small blues on the Isle of Portland
I had only ever seen a Small blue butterfly (Cupido minimus) twice before my recent trip to Weymouth, the first time back in the summer of 2018 during a visit to a friend in East Sussex (see Small and blue, 27 July 2018) and the second time in 2019, during a bird club trip to Salisbury Plain (Birding on Salisbury Plain, 13 May 2019). And I hadn’t expected to see them on this recent trip but Nature played a blinder!
I was over the moon to see Small blues three days in a row, all on the Isle of Portland but all in locations where I never expected to find them. The first was on Friday 8 May in King Barrow Quarry, where I was amazed to spot three in one small area, a little colony.
The second was the following day, Saturday the 9th, in Tout Quarry, this time a single butterfly that just appeared on the path below me as if by magic.
And the third, on Sunday 10th, once again appeared as if conjured up out of thin air, this time on the grass below the National Coastwatch building near the coastal path that runs along Portland’s west cliffs.
The one time I actually went looking for Small blues, and spent two hours walking almost every small path through the Broadcroft Butterfly Reserve, where these butterflies are supposed to live, I saw none. Which only made me even more grateful to have experienced the previous three totally unexpected sightings.
18 Monday May 2026
Posted in insects
Tags
British butterflies, butterfly, Dorset butterflies, Isle of Portland butterflies, Lasiommata megera, Wall, Wall butterfly
My decision to head to Weymouth and Portland for a week from the 7th to the 14th of May was a last minute one; I had booked somewhere else but the weather there was forecast to be mostly wet so I cancelled that and headed south to Dorset instead. I hadn’t checked which butterfly species I might see there; I just knew that if it rained in Weymouth, I could always go birding.
When the Dorset weather turned out mostly dry, if not always particularly sunny, I knew I had to head to the locations on the Isle of Portland where I’ve previously found butterflies, and one of the first I saw there was the Wall (Lasiommata megera). Checking now, I see that the first generation adults usually emerge in late April – early May, so my timing was perfect.
Most of the Walls I spotted, in Tout and King Barrow quarries, at the Broadcroft Butterfly Reserve, and along the coastal path above the west cliffs, were constantly active, the majority males flying back and forth in search of females but, occasionally, one would pause long enough and close enough for me to get a few photos. These are they.
15 Friday May 2026
Posted in insects
I had to go all the way to the Isle of Portland to see my first Common blue butterflies of the year!
Nah, not really. It just so happened that I didn’t spot any locally before I headed down to Dorset for another wonderful week of wildlife spotting, based in my lovely favourite guesthouse in Weymouth. I returned home yesterday, and this morning I went for a walk to my local Lavernock Nature Reserve, where I saw a couple more Common blues, despite a cool nor-westerly and not a lot of sun.
In case you’re not overly familiar with these butterflies, the one in my first photo is a male; they always have completely blue upper wings. The butterfly in my second photo is a female; they are often quite brown but this particular specimen had a lot more blue in her upper wings. And below is a side view, showing the pattern of spots on the lower wings. Distinguishing one species of blue butterfly from another can sometimes be all about recognising the patterns on the underwings.
09 Saturday May 2026
Posted in insects
Tags
British butterflies, butterfly, influx of Painted ladies, migrant butterfly, migrating Painted ladies, Painted Lady, Vanessa cardui
I wasn’t in the UK for the last huge influx of Painted ladies (Vanessa cardui) in the spring of 2009, when an estimated 11 million butterflies arrived here (Life Cycles of British & Irish Butterflies, p.241) but, in the last couple of weeks of April this year, we experienced a much smaller influx of this amazing migrating species.
This type of influx is subject to weather conditions; the butterflies take advantage of strong southerly winds to fly from sub-Saharan Africa across the Saharan Desert and the Mediterranean Sea to southern Europe and then onwards to more northerly locations, including Britain. (These weather conditions also see an increase in migrant moths arriving in southern Britain, in car owners reporting a thin covering of Saharan dust on their vehicles, and, sometimes, in murky skies and spectacular sunsets.)
I spotted my first two Painted ladies of the year at Cosmeston Lakes Country Park on 30 April, my bumper day of new sightings, as described in my last two blogs. ‘Nice’, I thought, and didn’t really expect to see a lot more, though I did notice reports on social media of large numbers of sightings across southern England.
Then, last Saturday, 2 May, as I walked the paths through the various fields at Cosmeston, Painted ladies just kept on appearing, as if by magic. My personal count after a couple of hours was 16, though I didn’t cover all the tracks around the park and I’m fairly sure there were many more I didn’t see. This number was certainly higher than I’d ever seen in one day before.
And you might be wondering what happens to all these butterflies? Well, according to Life Cycles of British & Irish Butterflies, research has shown that they breed here in Britain and their offspring migrate south again in the autumn. It’s estimated that, in the spectacular influx of 2009, as many as 21 million Painted ladies embarked on the return journey to Africa. Just incredible!
08 Friday May 2026
Posted in insects
≈ Comments Off on A bumper day, part 2
Tags
Aglais urticae, British butterflies, butterfly, Red Admiral, Small tortoiseshell, Vanessa atalanta
As I mentioned in yesterday’s blog, A bumper day, part 1, last Thursday proved to be a brilliant day for wildlife sightings, in particular for my first 2026 sightings of several flying creatures. These included this beautiful Small tortoiseshell (Aglais urticae), which was a particularly exciting find as, sadly, these butterflies are quite a rarity nowadays in my area and, indeed, throughout Wales. The 2025 UKBMS (United Kingdom Butterfly Monitoring Scheme) report shows a 62% decrease in reported sightings of this species at the monitoring sites in Wales in the 10 years prior to 2025. In England, the statistics are even worse, with a 78% decrease in the previous 10 years’ sightings, and an even more alarming 88% decrease in sightings in the 50 years from 1976. You can perhaps understand why I was so excited to see this particular butterfly.
I had already seen my first Red admiral (Vanessa atalanta) of the year before last Thursday’s walk, but that had been a fleeting glimpse of a single, rather tatty looking creature, so it was nice to see this pristine specimen, likely a recent arrival on the strong southerly winds that have recently been blowing migrant Lepidoptera to the southern shores of Britain. There was one other new butterfly species seen during that bumper day of new sightings but it deserves its own blog post so will appear here tomorrow.
06 Wednesday May 2026
Posted in insects
Monday week ago I had a lovely meander around Lavernock Nature Reserve, a local Wildlife Trust site perched on a cliff-top high above Lavernock Point and St Mary’s Well Bay on the edge of the Bristol Channel. It was a warm sunny day so I was hoping for lots of butterflies, and I was certainly not disappointed. In fact, I was thrilled when checking one of the places where I’d previously seen this particular butterfly species, to have my first Dingy skipper of the year pop up to defend its little piece of dirt. And, since then, I’ve also seen more – four one day, one the next – during walks around Cosmeston Lakes Country Park.
05 Tuesday May 2026
Posted in insects
≈ Comments Off on NFY: Small copper
Here’s another very early, surprise, spring sighting, my first Small copper butterfly (Lycaena phlaeas) of 2026. I don’t usually see these beauties until early to mid May but this gorgeous glistening creature popped up to defend its little territory when I walked across a local horse paddock ten days ago, on 25 April. Small coppers are one of my favourite butterflies so I’m very much looking forward to seeing more in the weeks to come.
24 Friday Apr 2026
Posted in insects
≈ Comments Off on NFY: Green-veined white
Tags
British butterflies, butterfly, Green-veined white, Green-veined white butterfly, Pieris napi, spring butterflies
It’s been 13 days since I found this Green-veined white butterfly (Pieris napi), my most recent new species for 2026, and what a little beauty it was, a brilliant white but with the subtle grey-black markings on its upper wings that are typical of this butterfly. Of course, I’ve seen many more of these since that first sighting, and they’ll all be busy finding butterflies of the opposite sex, mating and egg-laying; this species has two generations each year, so there’s no time to relax and enjoy the flowers!
